1. Field of the Invention
The present invention relates to a portable power cutter having two rotating operative components rotationally driven by a prime mover such as a small air-cooled two-cycle gasoline engine or an electric motor. More particularly, the invention relates to a power transmission mechanism for a portable power cutter having, as the rotating operative components, an operative cutter (having cutting means such as a cutter blade) and a dust suction-discharge fan for discharging the dust resulting from the cutting operation.
2. The Prior Art
In prior art portable power cutters of this type, there has heretofore been proposed and used a body or frame carrying a prime mover, an operative cutter including cutting means, such as a cutter blade, a safety cover, etc., and a dust suction-discharge fan for discharging by sucking the dust resulting from use of the cutting means on concrete-formed material or the like.
In such conventional portable power cutters, the cutting means is driven by the prime mover to rotate, and the driving force of the prime mover is also used to rotationally drive the dust suction-discharge fan.
In the conventional power cutters, however, the cutting means is driven by the prime mover to rotate at a reduced speed and the dust suction-discharge fan is also driven by the prime mover at a reduced rotational speed or at the same speed. Accordingly, the dust suction-discharge fan is likely to be incapable of exhibiting sufficient dust suction-discharge performance.